Grade A Lakes, Excellent

3,471 lakes (24% of lakes we track)

A-grade lakes are the low-nutrient, low-algae end of the working set. 3,471 lakes (24% of lakes we track) pull an A. The letter does not grade Secchi depth, and it is blind to mercury, PFAS, and bacteria.

A B C D F

3,471

Grade A lakes

States in this list

MN 100

Lake	County	State	Clarity	Depth	Fish
Rainy Lake	Cass	MN	13.9 ft	29 ft	0
Crane Lake	Otter Tail	MN	9 ft	43 ft	0
Lobster Lake	Douglas	MN	13 ft	65 ft	18
East Fox Lake	Crow Wing	MN	16.4 ft	65 ft	15
Deep Portage Lake	Cass	MN	15.4 ft	105 ft	9
Clearwater Lake	Cook	MN	29 ft	65 ft	0
Clearwater Lake	Wright	MN	9.8 ft	73 ft	17
Clearwater Lake	Crow Wing	MN	13 ft	54 ft	16
Clearwater Lake	Clearwater	MN	10 ft	65 ft	14
Lower Hay Lake	Crow Wing	MN	18.5 ft	100 ft	21
Latoka Lake	Douglas	MN	19 ft	108 ft	16
Little Birch Lake	Todd	MN	13 ft	89 ft	20
North Long Lake	Crow Wing	MN	15.1 ft	97 ft	18
Bad Medicine Lake	Becker	MN	25 ft	84 ft	13
Mud Lake	Becker	MN	12.5 ft	34 ft	16
Big Lake	Beltrami	MN	9.7 ft	35 ft	17
Big Lake	Carlton	MN	10 ft	25 ft	9
Big Lake	Sherburne	MN	13.6 ft	48 ft	14
Big Lake	St. Louis	MN	8.2 ft	22 ft	8
Big Sugar Bush Lake	Becker	MN	16.5 ft	42 ft	13
Pelican Lake	Otter Tail	MN	16.4 ft	55 ft	20
Pelican Lake	Crow Wing	MN	14.3 ft	104 ft	17
Fullers Lake: East Basin	Beltrami	MN	15 ft	-	0
Birch Lake	Ramsey	MN	5.9 ft	-	0
Birch Lake	Wright	MN	15 ft	52 ft	9
Birch Lake	Cook	MN	18 ft	69 ft	3
Birch Lake	Cass	MN	14 ft	45 ft	14
Round Lake	Aitkin	MN	14.5 ft	125 ft	18
Round Lake	Crow Wing	MN	13.5 ft	51 ft	20
Round Lake	Cook	MN	16.5 ft	45 ft	5
Round Lake	Beltrami	MN	18 ft	38 ft	0
Round Lake	Otter Tail	MN	11.2 ft	24 ft	0
Round Lake	Becker	MN	10 ft	69 ft	18
Round Lake	Anoka	MN	8.9 ft	-	0
Ada Lake	Cass	MN	14 ft	60 ft	16
Pike Lake	Cook	MN	17.4 ft	45 ft	7
Whitefish Lake	Crow Wing	MN	14.4 ft	138 ft	23
Whitefish Lake	Beltrami	MN	12.5 ft	30 ft	12
Horseshoe Lake	Crow Wing	MN	14.4 ft	56 ft	11
Horseshoe Lake	Cass	MN	8.9 ft	12 ft	0
Horseshoe Lake	Isanti	MN	3.5 ft	-	0
Farm Lake	Lake	MN	5.5 ft	56 ft	12
Washburn Lake	Cass	MN	14.1 ft	111 ft	21
Long Lake	Stearns	MN	13.5 ft	28 ft	5
Long Lake	Kandiyohi	MN	10.5 ft	46 ft	15
Long Lake	Clearwater	MN	20.5 ft	80 ft	15
Long Lake	Cass	MN	21.5 ft	115 ft	14
Long Lake	Beltrami	MN	20 ft	87 ft	11
Long Lake	Otter Tail	MN	12.3 ft	128 ft	16
Long Lake	Becker	MN	19.5 ft	61 ft	16
Long Lake	Hubbard	MN	11.2 ft	135 ft	14
Long Lake	Otter Tail	MN	12.1 ft	88 ft	1
Long Lake	Beltrami	MN	10 ft	83 ft	0
Long Lake	Otter Tail	MN	11.6 ft	73 ft	17
Long Lake	Beltrami	MN	14 ft	-	0
Long Lake	Itasca	MN	16.7 ft	72 ft	10
Long Lake	Itasca	MN	16.9 ft	85 ft	12
Dead Lake	Hubbard	MN	16 ft	34 ft	9
Dead Lake	Otter Tail	MN	10.2 ft	65 ft	18
Unnamed Lake	Crow Wing	MN	6.6 ft	-	0
Unnamed Lake	Nicollet	MN	5.6 ft	35 ft	6
Unnamed Lake	Sherburne	MN	13 ft	43 ft	7
Maple Lake	Cass	MN	13.3 ft	45 ft	0
Maple Lake	Douglas	MN	14.1 ft	78 ft	17
Maple Lake	Itasca	MN	15.3 ft	39 ft	13
West Twin Lake	Crow Wing	MN	13.3 ft	42 ft	12
West Twin Lake	Cook	MN	9.8 ft	37 ft	2
Shallow Lake	Itasca	MN	16.4 ft	85 ft	12
Shallow Lake	Hubbard	MN	8.2 ft	10 ft	13
Trout Lake	Itasca	MN	18 ft	157 ft	9
Trout Lake	Cook	MN	18.4 ft	77 ft	6
Detroit Lake	Becker	MN	14 ft	89 ft	19
South Sturgeon Lake	St. Louis	MN	2.5 ft	43 ft	10
Sallie Lake	Becker	MN	13 ft	50 ft	16
Deer Lake	Beltrami	MN	11 ft	42 ft	14
Deer Lake	Otter Tail	MN	12.3 ft	26 ft	16
Deer Lake	Itasca	MN	8.9 ft	50 ft	15
Deer Lake	Hubbard	MN	12.8 ft	9 ft	8
Deer Lake	Itasca	MN	13.1 ft	121 ft	17
Chippewa Lake	Douglas	MN	14.8 ft	95 ft	19
Twin Lake	Washington	MN	13 ft	-	0
Otter Lake	Ramsey	MN	11.5 ft	21 ft	12
Lida Lake	Otter Tail	MN	14 ft	58 ft	20
Five Island Lake	Itasca	MN	13 ft	33 ft	10
Schram Lake	Beltrami	MN	3.9 ft	-	0
Cowdry Lake	Douglas	MN	17.1 ft	52 ft	19
Big Spunk Lake	Stearns	MN	10 ft	38 ft	19
Ossawinnamakee Lake	Crow Wing	MN	20 ft	63 ft	18
Florida Lake	Kandiyohi	MN	12.3 ft	40 ft	18
Clear Lake	Crow Wing	MN	18 ft	63 ft	15
Clear Lake	Aitkin	MN	15 ft	24 ft	14
Clear Lake	Itasca	MN	14.9 ft	30 ft	9
Clear Lake	Washington	MN	14 ft	27 ft	6
Spectacle Lake	Isanti	MN	13.8 ft	51.5 ft	12
Garden Lake	Lake	MN	5 ft	55 ft	12
Marion Lake	Dakota	MN	7 ft	21 ft	14
Bear Lake	Lake	MN	17.4 ft	31 ft	4
Sullivan Lake	Morrison	MN	10.8 ft	57 ft	18
Emerald Lake	Beltrami	MN	9.5 ft	-	0
Vermont Lake	Douglas	MN	14.1 ft	59 ft	11

Showing 100 of 3,471 Grade A lakes.

Frequently Asked Questions

How many lakes have a grade of A?

There are 3,471 Grade A (Excellent) lakes across the 49 states and 2 Canadian provinces LakeQuality covers. That is 24% of the 14,370 lakes we track. Lakes without enough recent nutrient or algae samples are published as Not Rated — they are not in this count and they are not an F.

What does a Grade A mean?

Grade A means nutrients and algae are in EPA’s Good condition class for that lake’s ecoregion. Water clarity (Secchi depth) is measured and shown on the lake page; it is not the letter. An A is not a swimming or fish-consumption clearance — the grade is blind to mercury, PFAS, and bacteria.

Featured Grade A Lakes

Rainy Lake

Cass County, MN · 13.9 ft clarity

Crane Lake

Otter Tail County, MN · 9 ft clarity

Lobster Lake

Douglas County, MN · 13 ft clarity

East Fox Lake

Crow Wing County, MN · 16.4 ft clarity

Deep Portage Lake

Cass County, MN · 15.4 ft clarity

Clearwater Lake

Cook County, MN · 29 ft clarity

Source: EPA National Aquatic Resource Surveys, 2026.